Rig retargeting for 3D animation

Abstract

This paper presents a new approach to facilitate reuse and remix-ing in character animation. It demonstrates a method for automati-cally adapting existing skeletons to different characters. While the method can be applied to simple skeletons, it also proposes a new approach that is applicable to high quality animation as it is able to deal with complex skeletons that include control bones (those that drive deforming bones). Given a character mesh and a skele-ton, the method adapts the skeleton to the character by matching topology graphs between the two. It proposes specific multireso-lution and symmetry approaches as well as a simple yet effective shape descriptor. Together, these provide a robust retargeting that can also be tuned between the original skeleton shape and the mesh shape with intuitive weights. Furthermore, the method can be used for partial retargeting to directly attach skeleton parts to specific limbs. Finally, it is efficient as our prototype implementation gen-erally takes less than 30 seconds to adapt a skeleton to a character. Index Terms: I.3.7 [Computer Graphics]: Animation — [I.3.5]: Computer Graphics—Geometric algorithms, languages, and sys-tems 1